What is the difference between hardware accelerator and emulator?

what is the difference between hardware accelerator and emulator?

Re: design verification.

Emulation is a broad term that can be used in different ways in computing.
RUnning a program on FPGAs to replace a software simulator is emulation. Taking a trap when a certain instruction is issue in cpu and the trap handler executes the series of instructions to emulate the issued instruction. That's another form of emulation. Converting a binary code from other ISA on the fly to execute it on the computer with different architecture is also emulation.

Anything that uses specialized hardwares replacing software to make the process faster is hardware acceleration.

When it comes to the design process, emulation is running the test program on the hardware such as a bunch of FPGAs instead of doing so on the software simulator and it is a type of hardware acceleration by nature. In this case, the terms, hardware acceleration and emulation, are interchangable, although we actually don't use the term, hardware acceleration

Re: design verification.

Hardware accelerator are devices used along with controller to speed up the overall execution speed.
E.g DMA(direct memory access)
Usage of cpu and FPU in a single controller.
Any accelerator in the form of co-processor,
DSP etc.

Emulators
An emulator is a virtual-copy of a physical device. They are used as substitute of the original hardware that will be used as a final project hardware.
This is basically used to test the complete functionality of software and to confirm if it works on the real hardware without problem

Re: design verification.

finally..i got clear idea about it..thanku